METHOD FOR OBTAINING A GRANULAR SORBENT FOR LITHIUM RECOVERY FROM LITHIUM-CONTAINING BRINES UNDER CONDITIONS OF PRODUCTION OF COMMERCIAL LITHIUM PRODUCTS Russian patent published in 2018 - IPC B01J20/30 B01J20/02 B01J20/08 

FIELD: chemistry.

SUBSTANCE: invention relates to preparation of granular inorganic sorbents. To obtain a sorbent in the form of a powder LiCl·2Al(OH)₃·mH₂O (DHAL-Cl) use a lithium-containing solution of aluminum chloride. To obtain the above solution, six-chloride aluminum chloride is dissolved in aqueous solutions containing commercial lithium compounds: LiCl, LiOH·H₂O, Li₂CO₃, or solutions containing solutions thereof. Synthesis of DHAL-Cl is carried out at an atomic ratio of Al:Li in the reaction mixture of 2.0:2.3. Solution of sodium hydroxide is added to the reaction mixture to pH 7. DHAL-Cl formed is separated by centrifugation, is pulped in water, removing excess LiCl, and subjected to a two-stage drying first in a fluidized bed regime, then in a vacuum. After drying and grinding, the paste is prepared by mixing DHAL-Cl with the polyvinyl chloride solution in a chlorinated organic solvent. Solvent used is methylene chloride, trichlorethylene, or tetrachlorethylene, or mixtures thereof. Resulting paste is extruded through spinnerets with countercurrent supply of heated air. After air degassing stage, the extrudate enters the vacuum degassing stage. Further, the extrudate is subjected to crushing and classification with the return of the fine fraction to preparation of the paste. Granules with a size of 1–2 mm are pelletized, and screenings are sent to prepare the paste. Air, cooled after degassing of the extrudate, saturated with vapors of organochlorine solvent and water, is directed to compression at a pressure of 6 at, while cooling the air flow to -3 °C. Vapors of solvents and water formed during condensation liquid phase are separated. Gas stream, freed from the condensed phase, is subjected to deep cooling to -15 °C. Solid phase of ice is separated and the liquid phase of the organochlorine solvent is decompressed by heating to 0 °C. Liquid phase from the stage of decompression and deep cooling is used to prepare the paste. Cleaned and dried air stream is heated to 120–140 °C and used in the degassing step of the extrudate.

EFFECT: invention provides an increase in the efficiency of the sorbent production process in formation of lithium compounds.

1 cl, 6 dwg